Various products are manufactured by an injection molding machine.
In the research and development of medicine and chemicals, sample storage tubes are used extensively in storing a large number of samples. For example, scientists prepare a large number of samples for a comparative experiment with slightly changing conditions such as blending amount, and they use storage tubes for storing the samples for a required period of time while evaluating them. As the sample storage tube, a micro tube is used.
A plurality of micro tubes are independent of each other and these are arrayed in the rack used as a micro tube array set. The micro tube is a sample storage tube whose height is about several centimeters to 10 centimeters and is made of plastic resin. The micro tube can be used single independently and can be used as micro tube array for storing many samples at the same time arrayed in the rack. Recently, the micro tube array set in which plurality of micro tubes are arrayed in the rack becomes popular.
For example, the micro tube type sample storage tube is manufactured by the injection molding machine.
FIG. 17 is a schematic view showing the micro tube type sample storage tube having the outer screw shown in the prior art JP4696186.
As shown in FIG. 17, the sample storage tube 10 is a micro tube with the tube body installed in the outer element (jacket) 12. The sample storage tube 10 comprises a cylinder shape tube body 11 inserted to the outer element 12, an outer element 12, a seal object 13 for enhancing the air tightness and a lid 14 for capping the opening of the tube body. The sample storage tube 10 provides airtightness and writable ability by the outer element 12 and the lid 14 to the cylinder shape tube body 11.
The sample storage tube 10 caps the opening of the tube body 11 by the combination of the outer element 12 and the lid 14. In this example, the sample storage tube is what is called the “outer screw type” in which the outer screw is provided on the upper portion of the outer element 12 while the inner screw is provided on the inner side surface of the lid 14.
If the outer type sample storage tube 10 does not employ the seal object 13 and only the lid 14 contacts to the opening of the tube body 11, the airtightness of the tube body 11 may be deteriorated. Outside air can pass through the fine gap between the opening edge of the tube body 11 and the lid 14 because physical manufacturing errors such as manufacturing error in the tube body opening edge and manufacturing error in the inner surface of the lid 14 exist and cannot be not avoided physically.
This ventilation may affect the preservation state of the sample in the tube body 11. Therefore, the seal object 13 may be employed to secure the airtightness. In this example, the seal object 13 is provided as the independent element located between the opening of the tube body 11 and the lid 14. As the other example, the seal object 13 can be provided as the inner object of the lid 14 by embedding in the inner surface of the lid 14.
The material of the seal object 13 should be an elastic material such as silicone plastic rubber, natural rubber and thermal plastic elastomer. When the seal object 13 located between the opening of the tube body 11 and the inner surface of the lid 14 is pressed and pinched by screwing the outer element 12 and the lid 14, the seal object 13 made of elastic material is deformed by the pressure. When the lid 14 is screwed onto the tube body 11, the deformation of the seal object 13 gets bigger than the manufacturing error in the opening of the tube body 11 and the inner surface of the lid 14. Therefore, the bad effect from the manufacturing error in the opening of the tube body 11 and the inner surface of the lid 14 can be eliminated by the deformation of the seal object 13.
In this example, the outer element 12 is made of plastic resin that can turn its color from black to white by laser irradiation. The sample storage tube 10 is used for a micro tube array set in which a lot of sample storage tubes 10 are arrayed in order to store a lot of samples. Therefore, the micro tube array having a simple cylinder structure is not enough because the sample storage tube 10 should have the required function and structure such as an information writable area on the outer side surface and a lid for enclosing the sample with airtightness. The sample storage tube having a simple cylinder structure in the prior art as shown in FIG. 17 is equipped with an outer element 12 in order to obtain the required function and structure as the sample storage tube 10.
FIG. 18 is a schematic view showing the micro tube type sample storage tube having the inner screw shown in the prior art JP4696186.
As shown in FIG. 18, the sample storage tube 20 comprises a micro tube 21 installed in to the outer element 22, a seal object 23 for enhancing the air tightness and a lid 24 for capping the opening of the tube body the same as that of FIG. 17. The lid 24 of the sample storage tube 20 is screwed into the inner screw installing near around the upper opening. In this example, the sample storage 20 is “the inner screw type”, which the inner screw is provided on the inner side surface of the upper opening of the tube body 21, and the outer screw is provided on the outer side surface of the lid 24.
If the inner type sample storage tube 20 does not employ the seal object 23 and only the lid 24 contacts to the opening of the tube body 21 directly, the airtightness of the tube body 21 may be deteriorated. Outer air can pass through the fine gap between the opening edge of the tube body 21 and the lid 24 because physical manufacturing errors such as manufacturing error in the tube body opening edge and manufacturing error in the inner surface of the lid 24 exist and cannot be not avoided physically. The inner screw type as well as the outer type requires the seal object 23 in order to secure the airtightness. In this example, the seal object 23 is provided as the independent element located between the opening of the tube body 21 and the lid 24. As the other example, the seal object 23 can be provided as the inner object of the lid 24 by embedding it into the inner surface of the lid 24.
Prior art 1: JP4696186